This is an Arduino "sketch". If you already use Arduino, you should beable to load the Watch.ino file into the IDE and compile and loadit. Read the start of Watch.ino for information on how to connect theLEDs and switches required.Personally, I use the arduino-mk project, which lets me use GNU maketo build and upload projects, allowing them to be built with myfavorite IDE rather than having to use the Arduino IDE (meaning I getbuilds done with -j10 without having to figure out who to do that inthe Arduino IDE, so they're much faster). You'll want to edit theMakefile to set the ARDUINO_* and BOARD_TAG variables properly.